Afghans are more pessimistic about the direction of their country, less confident in the ability of the United States and its allies to provide security and more willing to negotiate with the Taliban than they were a year ago, according to a new poll conducted in all of Afghanistan's 34 provinces.

But residents of two key southern provinces that have been the focus of U.S. military operations over the past year say aspects of their security and living conditions have improved significantly since last December.

The new poll - conducted by The Washington Post, ABC News, the British Broadcasting Corp. and ARD television of Germany - found a particularly notable shift in public opinion in Helmand province, where Marines have been conducting intensive counterinsurgency operations. The number of people in Helmand describing their security as "good" jumped from 14 percent in a December 2009 poll to 67 percent now. Nearly two-thirds of Helmand residents now say Afghanistan is on the right track.

In Helmand and in neighboring Kandahar, the percentage of residents reporting threatening nighttime letters from the Taliban has been sliced in half. Public assessments of the U.S. military efforts in the area have also improved over the year, but 79 percent of people in the two provinces say American and allied troops should start their withdrawal next summer or sooner.

The changes in Helmand and Kandahar bolster claims by senior U.S. military officials, including Gen. David H. Petraeus, the top coalition commander, that the application of greater combat power and civilian assistance is starting to make a difference. But the results also lay bare the challenge that remains in encouraging more Afghans to repudiate the insurgency and cast their lot with the government.

"We clearly have to continue to provide the message to the Afghan people about why we're here and what it is that we want to do, not just for our own national objectives and coalition objectives but also for the people of this country and for the government of Afghanistan," Petraeus said Sunday in Kabul in an interview with ABC News about the poll.

Nationwide, more than half of Afghans interviewed said U.S. and NATO forces should begin to leave the country in mid-2011 or earlier. More Afghans than a year ago see the United States as playing a negative role in Afghanistan, and support for President Obama's troop surge has faded. A year ago, 61 percent of Afghans supported the deployment of 30,000 additional U.S. troops. In the new poll, 49 percent support the move, with 49 percent opposed.

"We want the Afghan forces to be able to control security so the foreign forces can leave," said Mohamed Neim Nurzai, 40, a farmer from Farah province who participated in the poll.

After a big drop last year, more than a quarter of Afghans again say attacks against U.S. and other foreign military forces are justifiable.

Overall, nearly three-quarters of Afghans now believe their government should pursue negotiations with the Taliban, with almost two-thirds willing to accept a deal allowing Taliban leaders to hold political office. Nearly a third of adults see the Taliban as more moderate today than they were when they ruled the country.

But the surge of U.S. troops and reconstruction funds in Helmand and Kandahar have improved many residents' perceptions of their quality of life. In Helmand, 71 percent now rate their living conditions as "good," up from 44 percent late last year, and 59 percent give positive marks to the availability of jobs, up from just 14 percent. In both southern provinces, public assessments of the availability of clean water and medical care are sharply higher than they were a year ago, running counter to trends elsewhere.

U.S. challenge

Although the findings in Helmand and Kandahar amount to a rare dose of hopefulness after nine years of war, the trends elsewhere illustrate the challenges and risks facing the Obama administration and its NATO allies as they seek to marginalize a resilient and adaptive insurgency. Those are among the issues being examined by the National Security Council in its review of the Afghan war, which will be presented to Obama in the coming days.

Senior U.S. military officials contend that the spread of Taliban activity to previously stable parts of the country does not pose an existential threat to the Afghan government, and they argue that security gains in the south will have a spillover effect elsewhere. But Afghans as a whole do not share that optimism.

For many Afghans, security concerns are rivaled by growing economic worries. Two-thirds view the availability of jobs as a problem, and nearly twice as many see things deteriorating as opposed to getting better.

"Aside from security, we have a lot of problems," said poll respondent Mohamed Nurzaid of Nimruz province. "Joblessness and the prices at the markets keep going up."

The U.S. government has spent more than $4 billion over the past year on reconstruction and economic development projects in Afghanistan. Two-thirds of Afghans say at least a good amount of the foreign aid money pouring into the country is being misdirected for personal gain by government officials.

For all the perceived pockets of improvement in Kandahar, 55 percent of respondents there say they have been asked for money or other payment from the police in exchange for favorable treatment, well above the national number of 21 percent. Most Kandahar residents feel their situation would only get worse were they to file a complaint about a public official.

Taliban's image

Support for the Taliban has jumped in Kandahar, where 45 percent now hold favorable views of the group. The same 45 percent of Kandahar residents see the Taliban as having a strong presence in their area.

But nationwide support for the Taliban remains tepid. Afghans overwhelmingly prefer the current government over the Taliban, and almost three in four continue to say it was good that the U.S. military toppled the Taliban in 2001, although that number is nine points lower than it was a year ago.

Despite the U.S. government's persistent skepticism of Hamid Karzai's leadership, more than six in 10 respondents feel the Afghan president is doing an "excellent" or "good" job. Fifty-nine percent of Afghans said they believe their country is headed in the right direction, a drop of 11 percentage points from a year ago.

Another change in the country over the year is a 13-point jump in the number of Afghans who say women's rights are suffering. While majorities of Afghans continue to support girls' schools, voting rights for women and their ability to work, 50 percent oppose women going outside their home unaccompanied by a male relative.

The poll is based on in-person interviews with a random national sample of 1,691 Afghan adults, conducted Oct. 29 to Nov. 13 by the Afghan Center for Socio-Economic and Opinion Research in Kabul, a subsidiary of D3 Systems of Vienna. Interviews were administered in Dari and Pashto, the country's two principal languages. The results have a margin-of-sampling error of plus or minus 3.5 percentage points.

chandrasek@washpost.com cohenj@washpost.com

Staff writer Ernesto Londono and special correspondent Javed Hamdard in Kabul and polling consultant Meredith Chaiken contributed to this report.